title: Simultaneous determination of alfentanil and midazolam in human plasma using liquid chromatography and tandem mass spectrometry.
abstract: A fast, sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of alfentanil and midazolam in human plasma has been developed and validated. Alfentanil and midazolam were extracted from plasma using a mixed-mode cation exchange solid phase extraction method, with recoveries of both compounds greater than 80% at 3 different concentrations (1, 10 and 100ng/ml). Compounds were analyzed on a C(18) column with a water and methanol mobile phase gradient with acetic acid as an additive, at a flow rate of 0.3ml/min. The working assay range was linear from 0.25 to 100ng/ml for each compound. The signal to noise ratio was 80 and 40 for alfentanil and midazolam, respectively, at the lowest concentration calibration standard, with less than 10% matrix suppression by human plasma at this concentration. Alfentanil and midazolam were stable in human plasma during storage at -80°C, processing, and analysis. The procedure was validated and applied to the analysis of plasma samples from healthy human subjects administered oral and intravenous alfentanil and midazolam.
authors.affiliation: Division of Clinical and Translational Research, Department of Anesthesiology, Washington University in St. Louis, St. Louis, MO 63110, United States.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kim
authors.forename: Amy
authors.initials: A
authors.lastname: London
authors.forename: Evan D
authors.initials: ED
authors.lastname: Kharasch
mesh_terms: D000284:Administration, Oral; D015760:Alfentanil / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D002851:Chromatography, High Pressure Liquid; D004347:Drug Interactions; D004355:Drug Stability; D004356:Drug Storage; D006801:Humans; D007275:Injections, Intravenous; D008874:Midazolam / Q000008:administration & dosage / Q000097:blood* / Q000493:pharmacokinetics; D012015:Reference Standards; D015203:Reproducibility of Results; D052616:Solid Phase Extraction; D013048:Specimen Handling; D053719:Tandem Mass Spectrometry
chemical_list: D015760:Alfentanil; D008874:Midazolam